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From: Jerry McAllister <jerrymc@clunix.cl.msu.edu>
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To: svein.h@lvor.halvorsen.cc (Svein Halvor Halvorsen)
Date: Mon, 14 Mar 2005 12:20:52 -0500 (EST)
In-Reply-To: <20050314172547.Y81679@maren.thelosingend.net> from "Svein Halvor
	Halvorsen" at Mar 14, 2005 05:28:26 PM
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cc: Jerry McAllister <jerrymc@msu.edu>
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cc: "Loren M. Lang" <lorenl@alzatex.com>
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Subject: Re: What's the easiest way to do a backup and verify?
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> 
> 
> * Jerry McAllister [2005-03-14 10:30 -0500]
> >  > [...] So then wouldn't a second dump of the same snapshot diffed to 
> >  > the tape device be a good for a verify?
> 
> >  No, because the condition of the files that you are dumping the second
> >  time is different from the first time.
> :
> >  Most places cannot afford to make file systems completely unavailable
> >  for periods of time long enough (several hours, up to a couple of days)
> >  to allow dump to be run twice without any changes being made to the
> >  file system.
> 
> 
> Note the OP's use of the word "snapshot". I think he is right! Or if he 
> isn't; it has nothing to do with the filesystem beeing changed, but rather 
> something to do with the way the backup is written to tape. However, I do 
> think snapshots could be used for exactly this.

But, if he is writing a snapshot, then why is he using dump?
I think he was using the word snapshot to imply the dump file.  
But, of course, I could be wrong.

////jerry